All About ASPEN

BURLINGTON, ONT.—In our continuing series of articles examining the broadcast industry’s transition to IP, this week Broadcast Engineering Extra spoke with Mo Goyal, director of product marketing for Evertz, to discuss the latest progress on ASPEN, the company’s IP transport protocol which it introduced at the 2015 NAB Show and how broadcasters are managing the overall transition to IP.

BROADCAST ENGINEERING EXTRA: What was the impetus for ASPEN? What prompted Evertz to develop this?

Mo Goyal

GOYAL: About three years ago, when we started looking at what the next trend was going to be, we looked at IP and 10Gig interfacing. Then we said that there was going to be this need for IP, 10Gig interfacing and such. As part of our road map for IP, we said, "OK, well if everything goes to IP and a 10Gig infrastructure, we need to look at production environments. As we worked with a key customer like ESPN, the environment that they were looking at was not just a simple SDI to IP mapping, there were some other things that needed to happen.

One of the things was the use of J2K within the facility, but then there was also the need to separate video, audio, and data. That's when we started looking at the foundations of ASPEN, where leveraging transport stream infrastructure—in the ecosystem that's available—to deliver separate video, audio, and data flows.

BEE: Why did you decide to base it on MPEG-2 Transport Streams?

GOYAL: MPEG-2 transport streams is a known entity that has existed for years, and will continue to exist. We use it to bring video/audio/data signals into a facility and to distribute video signals. There is a number of standards around MPEG-2 TS (IEC 13818-1, SMPTE ST 302 for audio, SMPTE ST 2038 for ANC data, and SMPTE 2022-2 for TS over IP). There is an inherent experience and knowledge base on transport streams. The one missing component was the ability to handle uncompressed video; that's really what ASPEN adds. It creates a framework to now carry uncompressed video over the TS. Because we have the available bandwidth, with 10Gig interfacing, it seemed to be the cleanest way to make that transition from SDI to IP.

BEE: Have you submitted ASPEN to SMPTE for review?

GOYAL: Yes. It's actually submitted as an RDD [Registered Disclosure Document]. It's been submitted to SMPTE and it's actually going through the balloting as we speak. It's going through the process of review by other members in SMPTE.

That's actually what the RDD process is and that's really where a number of other vendors have used in the past. It’s a way to get a proposal through a process and get it through a validation within SMPTE. It's an expedited process, without the full standard process, which could take a year or two but it still goes through a very similar process and validation.

It's not a rubber stamp; it's reviewed by members, voted, comments are provided, which are adopted. It then becomes a public document within the SMPTE space which means that anybody can implement it if they want and there are details on how to implement it. It's not proprietary.

BEE: Do you have any customers yet?

GOYAL: Yes. We have a number of customers: Game Creek, NEP Group, Time Warner Cable Sports and Discovery Communications are the current end users. (Editor’s note: NBC Sports announcedits deployment of ASPEN a day after this interview was conducted.) The ASPEN community has a number of vendors who are already on the committee. We're about to add a few others in the next week or two.

BEE: Were they existing Evertz customers that basically just moved over to ASPEN, basically?

GOYAL: Yes and no. Yes, they are adopting ASPEN because they see immediate benefits of IP and ASPEN.

BEE: ASPEN is basically all software, right?

GOYAL: It's an encapsulation format for uncompress video over MPEG-2 TS. It can be done in hardware, software or firmware. Today, it's implemented on Evertz hardware. We have a number of other partners that are part of the ASPEN community that are implementing to different form factors. ChyronHego and Vizrt are implementing it on their platform, whether it's software or through hardware means. We also have other vendors like Tektronix and PacketStorm that have implemented it, again, as combination of hardware and software.

BEE: What do you say to those customers who say they would rather wait for an industry agreed-upon standard?

GOYAL: There are customers that are trying to identify what the right choice is. To them, we say, "ASPEN has a great deal of traction. There's a growing community of 25-plus companies.” It’s being deployed today. We've got 20-plus installs of the technology over the last year and a half so they've been on air.

It's technology that is proven and is being used. ASPEN utilizes industry agreed on standards (IEC 13818-1, SMPTE ST 302 for audio, SMPTE ST 2038 for ANC data, and SMPTE 2022-2 for TS over IP) and completes the missing piece for uncompressed video over TS. To wait for that “ideal solution,” that could still be a couple years. There's still a lot of things that are being evaluated, whereas, at least with ASPEN, you're using a proven and common technology that works today that is open that people are using, versus wait, wait, wait.

If you wait, business conditions may change. It's one of those things where you have to make a decision. We believe strongly that IP is the right path, and that ASPEN is the most practical, most available technology that allows you to utilize IP today and future-proof yourself.

BEE: How does Aspen differ from other broadcast-based IP formats that are already available?

GOYAL: First and foremost you've got SMPTE 2022-6, which is the most common cited standard that's out there; it's been around for awhile. It's ideal for transport of video from point A to point B. What it's essentially doing is taking SDI, mapping it to an IP payload, and carrying it across. You'll get the video/audio data bundled into the SDI payload, and it gets sent across.

That’s great for transport applications. However, when you're into the production environment—which is really where IP is pushing towards for live events and such—your requirements are a little bit different. If I look at an SDI facility today, there is the need for audio embedders, de-embedders, an audio layer to separate those from the video. We can choose audio from one side and video from another and then merge them at the end. You need to have that flexibility in the production environment for video, audio, and even metadata layers being separated.

If we stick with the SMPTE 2022-6 we still need that existing infrastructure or that external infrastructure to separate it from the SDI payloads, which means that you really haven't leveraged IP; you’ve just made it a transport format to move from point A to point B. You still need to take it back SDI, then de-embed it or separate the video from audio in order to get the data that you want. From a practicality perspective, it's not ideal for the production environments.

Then you have Sony's Network Media Interface (NMI), which is essentially an adaptation of 2022-6, where it's still under single multicast but within that multicast, they separated the video, audio, and data. From the camera source, to server source, to the switchers, that information's already separated so that you don't need to have that external gear. It's a step forward from 2022-6 and it is designed for the live environment.

ASPEN builds upon that philosophy but basically separates video, audio, and data into separate streams and makes them a separate multicast so that I have complete flexibility of choosing through the switch fabric which stream I want—a video stream from one source, audio stream from another, and data from another source. Then I can send them to the destination. That's the flexibility that the production environment is used to. That's basically going back to the analog days in which you had a video level, audio level, and a data level.

BEE: What was your reaction to this week’s announcement of the formation of the Alliance for IP Media Solutions?

GOYAL: It was interesting. We know that it's really the community of vendors that are also looking at TR-03—which is the exercise that's being done through VSF (Video Services Forum) right now—which we're a party of as well. That's a long-term project that's starting to figure out how to sell the solution. It is interesting why the group was formed as it appears to mirror efforts that exist. Which, again, it's a VSF effort that has a number of participants on it, including us.

BEE: Will Evertz join this alliance?

GOYAL: That's something that we're looking at, but this is the relatively new information that they had officially formed an alliance.

BEE: Were you approached to join?

GOYAL: We were not. That's why we see it as an interesting exercise. It's a duplication of the VSF effort. We'll see as it develops, what impact they bring and what they're proposing. There's a great deal of similarities between the efforts in TR-03 and ASPEN. It's all being taken from an IP-only approach. We think there are significant benefits of taking the transport stream approach simply because it's a known quantity, a known infrastructure that's existed in the broadcast space for years, and it's quickly adaptable. We're still seeing what other additional benefits can be seen from 03 that can be offered above and beyond what ASPEN offers today.

BEE: One of the members of the alliance released a report this week that predicted it would take 10 years for broadcasters to complete the transition to IP. Do you agree with that assessment?

GOYAL: To be completely over IT, yeah. I think it's a transition that's happening right now. I think that we will start to see a significant high percentage of it within the next five years—I think 10 years is a long view.

BEE: You also have to define what “transition” means.

GOYAL: Exactly. I think right now, when we look at our current customer base, we see people are already making that transition to IP. When we look at the major players, they've already started that transition. It's really when the rest of the industry falls in suit when they're ready, I guess, and it makes financial sense for them.

BEE: What does ASPEN stand for?

GOYAL: Adaptive Sample Picture Encapsulation

Tom Butts

Tom has covered the broadcast technology market for the past 25 years, including three years handling member communications for the National Association of Broadcasters followed by a year as editor of Video Technology News and DTV Business executive newsletters for Phillips Publishing. In 1999 he launched for internet B2B portal Verticalnet. He is also a charter member of the CTA's Academy of Digital TV Pioneers. Since 2001, he has been editor-in-chief of TV Tech (, the leading source of news and information on broadcast and related media technology and is a frequent contributor and moderator to the brand’s Tech Leadership events.